Multimeter Mystery (many users having problem)

[vois2]

A curious problem has popped up in the Dell Forums.

A number of excited Dimension 8400 users went out and bought an eVGA nVidia GeForce 7900 GT when that card came out earlier in the month.

The 8400's stock power supply is a 350W unit providing 18A on the dual +12V rails. The max combined output is 28A on the two rails.

Every 7900 GT purchaser (to my knowledge) has come into the forums saying that they can't get the 7900 GT to work on their 8400. One guy even changed out to an Antec True Power 500W and still nada.

The 8400 previously and famously had no problems running the 7800 GT and 7800 GTX. The 7900 GT supposedly pulls less power thanks to nVidia's recent die shrink.

Anyway, I've brought home a multimeter as I happen to have an 8400 and I even have a spare, extra stock 8400 PSU. I have read a couple of online manuals for testing using a multimeter.

My understanding of electricity is pretty near zero, and I am not sure how to test the amperage on the rails. All the guides refer to is testing of voltage.

I'd like advice or tips on things to be sure to do when trying to learn multimeter information pertinent to the issue described above. Thanks so much for reading!

 

[blue68f100]

If the mm has the capabilites to measure current. It must be connected in series. Which means you will need to load the PS. There are extenders that you can buy so you don't have to cut your leads up. In order to get an accurate reading you will have to measure all of the leads to devices.

There are some DC clamp-on meters but they are expensive. There is also clamp-on attachments to use with your meter. Most all are AC, so check the specs closely.